Change From Baseline to the Last On-treatment Measurement in Urine Albumin to Creatinine Ratio (UACR) Levels Determined From the First Morning Void (FMV) Urine Collections Comparing Placebo to the Combined Paricalcitol Treatment Groups (1 Mcg and 2 Mcg). [ Time Frame: Baseline (within 1 week prior to first treatment) through 24 weeks of treatment ] [ Designated as safety issue: No ]

UACR is defined as the ratio: milligram of albumin per gram of creatinine. Baseline UACR was determined as the mean of the 3 UACR measurements from FMV urine collections obtained within 1 week prior to the day of the first dose of study drug. The last on-treatment measurement was the mean of the 3 UACR measurements obtained from FMV urine collections obtained within 1 week of the final week of treatment. The UACR data were log transformed prior to analysis.

Secondary Outcome Measures:

Number of Participants Achieving a 15% or Greater Reduction From Baseline to Last On-treatment Urine Albumin to Creatinine Ratio (UACR) Levels. [ Time Frame: Baseline (within 1 week prior to first treatment) through 24 weeks of treatment ] [ Designated as safety issue: No ]

Number of participants whose last on-treatment albumin to creatinine ratio (UACR) value was reduced at least 15% from the baseline value. Albumin values were determined from 24-hour urine collections from the baseline and last on-treatment visits.

Change From Baseline to the Last On-treatment Measurement in Albumin Levels Determined From 24-hour Urine Collection. [ Time Frame: Baseline (within 1 week prior to first treatment) through 24 weeks of treatment ] [ Designated as safety issue: No ]

The change is mean change from baseline to the last on-treatment value, with the data being log transformed prior to analysis. Albumin values were determined from 24-hour urine collections from the baseline and last on-treatment visits.

Change From Baseline to the Last On-treatment Observation in Intact Parathyroid Hormone (iPTH) Levels. [ Time Frame: Baseline (screening period) through 24 weeks of treatment ] [ Designated as safety issue: No ]

Participant has Type 2 Diabetes Mellitus and has been treated with at least one anti-hyperglycemic medication within the 12 months prior to the Screening Phase

Participant has been receiving a stable dose (i.e., same type and regimen) of ACEi and/or ARB for at least three months prior to the Screening Phase. However, participant may have switched to different brands but at equivalent doses during the three months prior to the Screening Phase.

Participant is not expected to begin dialysis for at least 6 months.

If female, participant is not breast feeding or is not pregnant.

For entry into the Treatment Phase, the participant must satisfy the following criteria based on the Screening laboratory values:

Urinary albumin to creatinine ratio (UACR) between 100 and 3000 mg/g as determined by the mean of the three first morning void urine specimens obtained within one week of each other

Corrected serum calcium level <= 9.8 mg/dL

intact parathyroid hormone (iPTH) value between 35-500 pg/mL

Glycosylated hemoglobin A1c (HbA1c) <= 12%

Serum albumin > 3.0 g/dL

Negative urine pregnancy test for female participants

Exclusion Criteria:

Participant has previously been on prescription-based vitamin D therapy within the six months prior to the Screening Phase.

Participant has a history of an allergic reaction or significant sensitivity to paricalcitol or to drugs similar to the study drug.

Participant has primary glomerulonephritis or secondary nephritis in addition to diabetic nephropathy.

Participant has had acute renal failure within 12 weeks of the Screening Phase, defined as an acute rise (of >= 0.5 mg/dL) in serum creatinine to > 4 mg/dL.

Participant has chronic gastrointestinal disease.

Participant has secondary hypertension.

Participant has poorly controlled hypertension.

Participant has a history of kidney stones.

Participant has a history of drug or alcohol abuse within six months prior to the Screening Phase.

Participant has evidence of poor compliance with diet or medication.

Participant has received any investigational drug within 30 days prior to study drug administration.

Participant is taking calcitonin, bisphosphonates, cinacalcet, glucocorticoids (except topical glucocorticoids), or other drugs that may affect calcium, or bone metabolism, other than calcium containing phosphate binder or female participants on stable (same dose and product for three months) estrogen and/or progestin therapy.

For any reason, participant is considered by the Investigator to be an unsuitable candidate to receive paricalcitol capsules or is put at risk by study procedures.

Participant is known to be human immunodeficiency virus (HIV) positive.

Participant has used known inhibitors or inducers of cytochrome P450 3A (CYP3A) within two weeks prior to study drug administration.

Contacts and Locations

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study.
To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below.
For general information, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT00421733